RU2341813C2 - Mobile land based two dimensional radar for scanning in meter range - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: present invention pertains to using, in radar, main and compensation antennae, multi-frequency generators of probing signals with output signals, which have non-linear frequency modulation and different carrier frequencies and pulse durations. The radar also employs a solid state transmitter, consisting of unsealed modules, insertion gain followers of the main and four compensation cants, two four channel self-balancing potentiometers, two devices for primary processing, device for secondary processing and coupling, imaging and control device, unit for combining and matching information with the corresponding connections.

EFFECT: wider functional capabilities; reduced labour input for manufacturing and cost.

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Description

The invention relates to radar and can be used in radar stations (radar) air traffic control and airspace control for detection, measurement of plane coordinates and recognition of air objects (IN), as well as the modernization of the radar meter range.

Known radar meter range of similar purpose [1, 2]. The disadvantages of these radars are low tactical, technical and operational characteristics, which is explained by the use of an outdated element base in them, which does not meet the requirements for modern radars.

The closest in technical essence and purpose to the proposed one is the radar circular survey of the meter range [3], adopted as a prototype.

The radar prototype (FIG. 1) contains a main antenna (OA) 1, a compensation antenna (KA) 2, a probing signal shaper (FZS) 3, a solid-state transmitter (TP) 4, a main channel receiver (PRO) 5, a compensation channel receiver ( PRK) 6, auto-compensator (AK) 7, primary processing device (UPR) 8, secondary processing and pairing device (BOC) 9, display, control and monitoring device (OUK) 10 with corresponding connections.

FZS 3 of the prototype generates two sequences of sounding signals at one carrier frequency with different modulations: linear frequency modulation and phase shift keying.

TP 4 is built on the basis of sealed modules filled with inert gas. PRO 5 and PRK 6 traditionally for meter radars are built according to a superheterodyne circuit with one frequency conversion.

Compensation of active noise interference (ACP) in the radar prototype is carried out using a three-channel correlation auto-compensator AK 7, using signals from three out of four KA 2 emitters, which alternately switch when OA 1 rotates, through a three-channel PRK 6.

A feature of the prototype is also the cooling of the hardware cabinet with low-power equipment located in it, together with TP 4, which is produced by the supply and exhaust ventilation equipment equipped with a refrigeration unit.

The disadvantages of the prototype are:

- the high complexity of manufacturing and the cost of TP 4, made by the technology of microelectronics in the form of a large number of sealed and filled with inert gas modules;

- a high likelihood of overheating in the hardware cabinet due to insufficient reliability of the refrigeration unit, which can lead to failure of the radar equipment;

- insecurity of the radar from the effects of the ACP along the back lobe of the radiation pattern OA 1;

- inconsistency with the modern requirements of a number of tactical, technical and operational characteristics (noise immunity, resolution and range accuracy, performance, reliability, etc.).

The technical result of the invention is to expand the functionality by increasing a number of tactical, technical and operational characteristics (detection probability, accuracy and resolution in range, noise immunity, performance, reliability, resource, etc.) while reducing the complexity of manufacturing and cost of the radar.

To achieve this result, to a known radar containing the main and compensation antennas, a probing signal shaper, a solid-state transmitter, main and compensation channel receivers, an auto-compensator, a primary processing device, a secondary processing and coupling device and a display, control and monitoring device with corresponding communications, additionally introduced a second auto-compensator and a primary processing device, a unit for combining and identifying information with the corresponding relationships. In this case, the probe signal generator is multi-frequency and has a sequence of probe signals with nonlinear frequency modulation at the output, the solid-state transmitter consists of leaky modules, the receivers of the main and compensation channels are direct amplification receivers, and the auto-compensators and the compensation channel receiver are four-channel. In addition, the cooling of the equipment cabinet, in which the solid-state transmitter modules are located, is carried out by the ventilation equipment built into the equipment cabinet without using a refrigeration unit.

To explain the operation of the invention, Fig. 2 shows a structural diagram of a radar, where it is indicated:

1 - main antenna (OA);

2 - compensation antenna (KA);

3 - shaper of sounding signals (FZS);

4 - solid-state transmitter (TP);

5 - receiver of the main channel (PRO);

6 - receiver compensation channel (PRK);

7 - the first auto-compensator (AK);

8 - the first primary processing device (UPR);

9 - device secondary processing and pairing (VOS);

10 - display device, control and monitoring (OUK);

11 - second auto-compensator (AK);

12 - the second primary processing device (UPR);

13 is a unit for combining and identifying information (OOI).

As can be seen from the structural diagram, the radar contains the main antenna (OA) 1, the compensation antenna (KA) 2, the driver of the probing signals (FZS) 3, solid-state transmitter (TP) 4, the receiver of the main channel (PRO) 5, the receiver of the compensation channel (PRK ) 6, the first and second auto-compensators (AK) 7 and 11, the first and second primary processing devices (UPR) 8 and 12, the secondary processing and pairing device (BOC) 9, the display, control and monitoring device (OUK) 10 and the combining unit and information identification (OOI) 13, and the output of the FZS 3 is connected to the input T 4, connected in series through OA 1 and PRO 5 at its first and second outputs, respectively, with the first inputs of AK 7 and 11 and the second inputs of UPR 8 and 12, the first inputs of UPR 8 and 12 are connected respectively with outputs of AK 7 and 11, second, third the fourth and fifth inputs of which are connected to the four outputs of the PRK 6, the four inputs of which are connected to the four outputs of the AC 2, and the outputs of the UPR 8 and 12 are connected respectively to the first and second inputs of the block OOI 13, the first output of which is connected to the input of the device OUK 10, and the second - with the input of the device BOC 9, input-output, to is connected to the input-output of the device OUK 10, and the output is the output of the radar.

Moreover, all the output signals of FZS 3 have nonlinear frequency modulation and various carrier frequencies and pulse durations, TP 4 consists of leaky modules, the structural unit of which is a radiator, and is located in a separate cabinet with its cooling fans, PRO 5 and PRK 6 are direct amplification receivers, and PRK 6 and AK 7 and 11 are four-channel. AK 7 and 11, UPR 8 and 12, VOS 9 and OUK 10 devices and the OOI 13 unit are combined in the cabinet of the operator’s workplace (RMO), made on the basis of a modern high-performance computer with built-in boards of analog-to-digital converters and signal processors.

The radar operates as follows.

To ensure high detection characteristics in the context of fluctuations in the effective scattering area (EPR) of airborne objects [4], to ensure the effect of "blurring" the interference zeros of the antenna pattern in the vertical plane [5], and also to ensure the effect of "blurring" the zeros in the speed characteristic Doppler system for moving targets selection [6] the sounding of space is carried out at several carrier frequencies (for example, f ₁ , f ₂ , f ₃ and f ₄ ) by long sequences (for detecting HE in the far zone) and short (for the detection of VO in the near zone) pulses emitted in a single sensing cycle T _s , as shown in Fig.3. Moreover, the frequency separation between pairs of long and short pulses at frequencies f ₁ and f ₃ or f ₂ and f ₄ is the signal bandwidth, which allows them to be processed in one UPR device with appropriate digital filtering. The frequency spacing f ₁ , f _{2 is} much greater than the signal bandwidth to provide effects of improving the characteristics of target detection and "blurring" of spatial and Doppler zeros.

To ensure high resolution and accuracy in range, all probe pulses generated in FZS 3 have nonlinear frequency modulation [7]. The sequence of probe pulses is entirely radiated at the beginning of the clock, in contrast to the radar prototype, where the near-field signal is emitted at the end of the clock. The separation of received information from the near and far zones is carried out by the carrier frequency, and not by time. This solution allows you to get rid of the false twin signals that occur in the radar prototype at ambiguous ranges from the radiation of near-field signals with large EPR VO.

Formed in FZS 3 pulses are amplified by power in broadband TP 4 and emitted OA 1 into space. The echo signals reflected from the VO through OA 1 enter the ABM 5, where they are frequency-selected, amplified, and converted into a digital code using a high-speed broadband analog-to-digital converter (ADC). From the outputs 1 and 2 5 ABM digital signals corresponding pair frequencies f ₁ and f _3, f ₂ and f _4, respectively fed to the first inputs AK 7 and 11 and second inputs 8 and 12 of the UPR.

AK 7 and 11 are, like PRK 6, four-channel and protect the radar from the effects of ACP coming from OA 1 through PRO 5, using signals that overlap the azimuthal background from the outputs of four KA 2 emitters through PRK 6 OA 1 from all directions, which allows you to simultaneously compensate for up to four sources of interference.

UPR 8 and 12 detect and measure the coordinates and radial velocity of VO (each at its own carrier frequency) in the far and near zones. In this case, the optimal filtering of the signal with non-linear frequency modulation allows you to select a short signal that corresponds to the accuracy and resolution in range, unattainable for the prototype. The operation of the radar at spaced carrier frequencies with coherent accumulation of the azimuthal packet allows the maximum possible resolution of signals from HE and passive interference, which ensures the best selection of moving targets due to Doppler resolution [6].

In addition, UPR 8 and 12 measure the amplitudes of the VO signals, detect ACP sources and measure their power, as well as perform mapping of reflections from local objects and hydrometeorological formation, which also contributes to the selection of useful signals.

The algorithms for the primary processing of information are implemented programmatically on signal processors installed in the computer.

The primary coordinates and radial velocities of the signals detected by the UOFs 8 and 12 of different frequencies are compared and identified in the OOI unit 13, where the signal with the maximum amplitude is selected (thereby increasing the probability of detection), and its coordinates are sent to the BOC 9 device for trace processing and display in the device OUK 10.

The BOC device 9 carries out trace processing of information [8], combining information from the OOI unit 13 and secondary information received from a radio interrogator or secondary radar that is interfaced with a radar, and automatically controls the operating modes of the radar and objects interfaced with it (radio altimeters and a radio interrogator or secondary radar), as well as the output of the processing results to the OUK 10 device and external complexes of automation equipment (KSA).

The device OUK 10 provides the display on the screens of the RMI primary and secondary information received from the blocks OOI 13 and the device BOC 9, the display of controls, control of the operating modes of the radar, its systems and radar mates, radio interrogator or secondary radar (via the BOC device 9) , as well as monitoring the operation of the radar when it is turned on, continuous monitoring during its regular operation and automated troubleshooting.

Thus, the implementation of a survey of space at several carrier frequencies by pulses with nonlinear frequency modulation, which required the use of a multi-frequency FZS in the proposed radar, the introduction of a second AK and UPR and a new OOI unit, made it possible to increase the detection probability, accuracy and resolution in range and ensure maximum suppression reflections from local objects.

The use of modern high-performance element base (ADCs, signal processors, computers) and modern optimal processing algorithms made it possible to simplify missile defense and missile defense, reduce the overall dimensions of the equipment, and more than double the radar performance for simultaneous tracking of airborne targets.

The introduction of the fourth channel in the PRK and AK led to increased radar protection from ACP.

The use of TP with leaky modules allowed to significantly reduce the complexity of their manufacture and increase reliability, which significantly reduces the cost of the radar and increases its resource.

A significant increase in the reliability of the radar is also facilitated by cooling the TP without the use of a refrigeration unit.

All of the above expands the functionality of the radar both when working in air traffic control and airspace control systems, and with the possible modernization of the old fleet of meter radars with bringing their characteristics to the modern level.

Information sources

1. Mobile radar P-18. M .: Military Publishing House of the Ministry of Defense of the USSR, 1978.

2. The Arms of Russia 2004. M.: Military Parade, 2004, Radar 1L13, p.673.

3. A mobile ground-based two-coordinate radar with a circular view of the meter wavelength range. Pat. RU 2256190, IPC G01S 7/00, 13/00, s. No. 2003121688/09 dated 07/14/2003.

4. G.M. Vishin. Multi-frequency radar. M .: Military Publishing House, 1973, pp. 24-35.

5. Handbook of radar. / Edited by M. Skolnik. Volume 1. Basics of radar. M .: Sov. Radio, 1976, pp. 60-66.

6. M.I. Finkelyptein. Basics of radar. M .: Sov. Radio 1983, pp. 237-263.

7. C. Cook, M. Bernfeld. Radar signals. M .: Sov. Radio, 1971, p. 239.

8.S.Z. Kuzmin. Digital radar. Kiev, KVITs, 2000, pp. 183-307.

Claims (1)

A mobile ground two-coordinate radar station (radar) of circular meter-wide viewing, containing the main and compensation antennas, a probing signal shaper, a solid-state transmitter, primary and compensation channel receivers, a first auto-compensator, a first preprocessing device, a secondary processing and coupling device and a display, control device and control, and the probe signal generator is connected through a solid-state transmitter to the main antenna, the output of which The first is connected through the receiver of the main channel to the first input of the first auto-compensator and the second input of the first primary processing device, the first input of which is connected to the output of the first auto-compensator, the second, third and fourth inputs of which are connected to the first, second and third outputs of the receiver of the compensation channel, whose four inputs connected to the four outputs of the compensation antenna, and the input-output of the display, control and monitoring device is connected to the input-output of the secondary processing and pairing device, in the output of which is the output of the radar, characterized in that it includes a second auto-compensator and a primary processing device, as well as a unit for combining and identifying information with the possibility of comparing the output signals of the first and second primary processing devices by coordinates, radial speed and amplitude, and the fourth output of the receiver the compensation channel is connected to the fifth inputs of the first and second auto-compensators, the second, third and fourth inputs of which are connected in parallel, the second output of the main receiver the channel is connected to the first input of the second auto-compensator and the second input of the second primary processing device, the first input of which is connected to the output of the second auto-compensator, the outputs of the first and second primary processing devices are connected to the corresponding inputs of the unit for combining and identifying information, the first and second outputs of which are connected, respectively , with the inputs of the display, control and monitoring device and the secondary processing and pairing device, in addition, the probe of the probing signals is multi-frequency and made with the possibility of forming a series of sequences of sounding signals with different carrier frequencies and pulse durations and non-linear frequency modulation, the solid-state transmitter consists of leaky modules and is located in a separate cabinet together with cooling fans, the receivers of the main and four compensation channels are direct amplification receivers , auto-compensators are four-channel, and devices for primary processing, secondary processing and pairing, display, control and control and the unit for combining and identifying information are made on the basis of a modern high-performance electronic computer (COMPUTER) with built-in boards of analog-to-digital conversion (ADC) and signal processors.

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